Preparing for a job interview, school exam, special event, music recital or business presentation is vital for success but what you consume before the performance can make a difference too. Meal choices can make or break your mental powers.

Protein power

While a biscuit or bagel can be fast for breakfast, nutrition scientists say eating nothing but carbs is a bad choice for a big day. A Massachusetts Institute of Technology study compared two groups who ate either a high-protein or high-carbohydrate breakfast. Two hours later the carb group had levels of the sleep-inducing amino acid tryptophan that were four times higher than the protein group. Add an egg to that breakfast biscuit and some peanut butter or smoked salmon to a bagel to boost protein content. Lean protein foods such as eggs, milk, Greek yogurt, chicken and fish support the production of neurotransmitters needed for smart thinking.

Brain cells crave choline

Found in egg yolks, the nutrient choline helps support the brain's messenger service and new memory cell production. Attention egg white omelet fans: Chances are you're not getting enough choline if you skip the yolk. Registered dietitian Elizabeth Ward said, "It's a nutrient that's frequently under-consumed by those who need it most. In fact, fewer than 10 percent of older children, men and women meet the recommended Adequate Intake for choline." One egg, which contains 125 milligrams of choline, can help close the gap.

B alert

B vitamins, such as folate or folic acid, play a key role in forming the brain’s memory cells and have been shown to improve alertness in adults. The vitamin can be found in orange juice, green vegetables, cantaloupe, and whole grain foods including those enriched with folic acid such as breads, cereals, pasta and rice.

Pay attention with tea

Coffee may be the go-to beverage for go-getters but too much caffeine can cause nervous jitters. So switch to tea. John Foxe, Ph.D. professor of neuroscience, biology and psychology at City College of the City University of New York found that theanine, an amino acid in the tea plant increases alpha brain-wave activity which induces a calmer, yet more alert, state of mind. Theanine is found in green, black and oolong teas.

Water for the brain

Dehydration can make you feel listless and lethargic and contribute to concentration problems. If your brain feels a bit fuzzy, you might just be thirsty.